Jim, I think the suggestion is that the descent stage *could* be programmed to right itself and lower itself gently. It has to have *some* amount of control function in it, since it has to indepedently maneuver itself away from the rover after it cuts the cables.

I wonder just how much mass might be available for a very small science package and a small transmitter that would relay meteorological and/or seismic data back to the rover, and thence through MRO back to Earth? You'd need some light, simple instruments, a small transmitter and a small antenna. How much would that weigh? And how much mass could MSL stand to be added to the overall package?

I don't think anyone really believes that such a capability will seriously be considered, but it's OK to at least think about it...

-the other Doug

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“The trouble ain't that there is too many fools, but that the lightning ain't distributed right.” -Mark Twain

I don't know why the "skycrane" (in basically its same configuration), couldn't just have landing leg extensions (straddling MSL) and actually land (eliminating the MSL hanging in air). Once landed, MSL could just be similarly reeled down a few inches to the surface, cut loose, and then drive away. That way, they still have their immediately rovable rover, without the dangerous in-air suspension.

The "legs" would have to have a shock absorbsion system and able to handle uneven terrain. Also, they would have to be folded and then deployed adding more failure modes.

Basically, the descent stage is landing a few meters above the surface.

It is doing exactly like you said"Once landed, MSL could just be ....reeled down a few inches to the surface, cut loose, and then drive away"

That's what it is doing, just without a gap between landing and lowering

I don't think anyone really believes that such a capability will seriously be considered, but it's OK to at least think about it...

This is complex enough, adding more weight and requirements is just not going to happen. Maybe the 2nd, 3rd, 4th Mars crane, but not the first. Gotta run before you fly.

If we want a seismometer, the best way to do that is to deploy a network, and that doesn't look likely any time soon with the demise of Netlander. This would be a great Mars Scout mission, if it could be made cheap enough, with just a dead simple imager and seismometers. 4 landers would give good coverage, with the option of putting one or two in "challenging" but beautiful locations.

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Space Enthusiast Richard Hendricks --"The engineers, as usual, made a tremendous fuss. Again as usual, they did the job in half the time they had dismissed as being absolutely impossible." --Rescue Party, Arthur C ClarkeMother Nature is the final inspector of all quality.

Also, MSL will probably avoid the descent stage since it will be leaking hydrazine

Are you sure about that...As I understand it , skycrane will fly away quite fast up and away after releasing MSL lander ,suddenly lightened by about 700 kg...whooosh! When it runs out of fuel ,poor thing will have some hight and speed so when it crashes it will burst any hydrazine reservoirs that may contain some residue of fuel...Why do you think it will be dangerous for MSL lander to go near crashed skycrane even if it had some hydrazine left in its reservoirs as long as it doesn't fire its "laser weapon" on it ? I would like to see that thing on Mars seen through the eyes of MSL...

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The scientist does not study nature because it is useful; he studies it because he delights in it, and he delights in it because it is beautiful.Jules H. Poincare

its "laser weapon"[/quote]Must have watched too many bad sci-fi movies years ago as one of my first thoughts was Marvin would probably suffer sudden incontinence were he to see MSL drive over the top of a dune towards him.

Curious on the significance of "53" in members tim53 and gallen_53. Maybe it's 42 equivalent in the professional UMSF community.

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